The most common and most likely answer to this crossword clue is the 7 letter word BOTTLER
I've seen this crossword clue in The Guardian
B
O
T
T
L
E
R
Buddy explains!

The straight part
We know that "One packaging 16 across" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case one packaging 16 across = bottler.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does BOTTLER mean?
BOTTLER noun- A person, company, or thing who bottles, especially in bulk.
- A truck used for transporting bottled goods in crates.
- A person who or group that fails to meet expectations, especially one prone to such failure.
- A Punchman's assistant who collects money ("bottle") from the audience.
- (often with "real") a person or thing that is excellent or admirable.